U.S. Pat. No. 8,181,895 B2 has disclosed a crusher having an adjustable eccentric unit, such that, in a manner dependent on the setting of the eccentric unit, the crushing member can perform crushing movements of different magnitudes. The crusher has a crushing cone which is seated on a cone axle, and the greater the eccentricity of the illustrated eccentric unit composed of a main eccentric bushing and an adjustment eccentric bushing, the greater the deflection of the cone axle from a machine central axis. In the case of relatively great deflection of the cone axle from the machine central axis, the crushing cone travels with a greater encircling crushing movement toward a crusher funnel, and the attainable grain size to which the material for crushing in the crusher can be reduced can be set by way of the eccentricity of the eccentric unit.
The setting is performed by way of an adjustment unit which acts by way of two concentrically running shafts on two pinions. Here, one pinion acts on the main eccentric bushing, and a further pinion acts on the adjustment eccentric bushing, wherein the two eccentric elements are fitted coaxially one inside the other and give rise to a variable crushing movement of the cone axle. Said movement corresponds to a wobbling movement, and the deflection in the wobbling movement can be set in a manner dependent on the rotational orientation of the two concentric eccentric bushings relative to one another. It is however disadvantageously necessary for the adjustment unit, which acts on the shafts for the respective drive of the eccentric bushings, to be permanently monitored. Furthermore, the construction with a hollow shaft and with a further shaft led through the hollow shaft is made up of numerous details, which are in particular susceptible to faults, and two toothings are necessary, which perform, and must adhere to, a transmission of torques and mutual phase positions, which are correspondingly to be set, from the shafts to the eccentric bushings.